Question

find 25th term from it term & 30th term from last
term of AP: 2,5,8,152​

Answer 1

Answer:

From 1st term,

a=2, n=25, d=(5-2) =3, a(n)=?

Now,

a(n) = a+(n-1)×d

a(n) = 2+(25-1)×3

a(n) = 2+24×3

a(n) = 2+72

a(n) = 74

From last term,

a=152, n=30, d=-3, a(n) =?

Now,

a(n) = a+(n-1) ×d

a(n) = 152+(30-1) ×(-3)

a(n) = 152+29×(-3)

a(n) = 152-87

a(n) = 65

Answer 2

Answer:

An=a+(n-1) d this is formula a=2 d=3 n=25

A25 =2+(25-1) 3

A25=2+(24) 3

A25= 2+72

A25=74